In cognitive radio systems (CRS) or systems that can perform dynamic spectrum access (DSA), the spectrum is managed by dynamically allocating different bands to different network nodes based on demand. The network nodes may belong to one network operator or they may belong to different network operators. Spectrum sensing, done by UEs, network nodes such as evolved Node Bs (eNBs) or Relay Nodes (RN), or a dedicated sensing node, may be used to determine whether a channel is available or occupied. This sensing information can assist in the management and allocation of different bands to control interference among the nodes.
In one embodiment, this spectrum may be managed by a Spectrum Manager (SM), which may dynamically allocate channels to nodes based on sensing reports collected from various nodes or dedicated sensors. The Spectrum Manager may be an entity that belongs to one network operator, in which case, the Spectrum Manager is responsible for managing only the bands allocated to the network operator. Alternatively, the Spectrum Manager may be a shared entity that is responsible for managing spectrum among multiple network operators.
Sensing from multiple locations enables the Spectrum Manager to allocate the spectrum.